Plasticized poly(vinylalcohol) and poly(vinylpyrrolidone) based patches with tunable mechanical properties for cardiac tissue engineering applications.

Polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) are the two most investigated biopolymers for various tissue engineering applications. However, their poor tensile strength renders them unsuitable for cardiac tissue engineering (CTE). In this study, we developed and evaluated PVA-PVP-based patches, plasticized with glycerol or propylene glycol (0.1 - 0.4%; v-v), for their application in CTE. The cardiac patches were evaluated for their physico-chemical (weight, thickness, folding endurance, FT-IR, swelling behaviour) and mechanical properties. The optimized patches were characterized for their ability to support in vitro attachment, viability, proliferation, and beating behaviour of neonatal mouse cardiomyocytes (CMs). In vivo evaluation of the cardiac patches was done under the sub-cutaneous skin pouch and heart of rat models. Results showed that the optimized molar ratio of PVA: PVP with plasticizers (0.3%; v-v) resulted in cardiac patches, which were dry at room temperature and had desirable folding endurance of at least 300, a tensile strength of 6-23 MPa and, percentage elongation at break of more than 250%. Upon contact with phosphate-buffered saline (PBS), these PVA-PVP patches formed hydrogel patches having the tensile strength of 1.3 to 3.0 MPa. The patches supported the attachment, viability, and proliferation of primary neonatal mouse CMs and were non-irritant and non-corrosive to cardiac cells. In vivo transplantation of cardiac patches into a subcutaneous pouch and on the heart of rat models revealed them to be biodegradable, biocompatible, and safe for use in CTE applications. This article is protected by copyright. All rights reserved.